JPS59190432A - Fuel injection control device for internal- combustion engine - Google Patents

Abstract

PURPOSE:To allow the fuel to be fed to an engine even when a controller is disabled and improve the reliability by controlling the control rack position by means of a variable resistor when the controller controlling the control rack positon of a Diesel engine by an electronic control circuit is disabled. CONSTITUTION:An abnormality detection section 5 is fed with a signal having a period of about 15 msec from a microcomputer, and when this signal is stopped, the condition is judged as abnormal. SW1 and SW2 are operated by the signal of the abnormality detection section 5. When a controller 2 is working normally, these switches are connected to the (a) side, and a control rack is controlled by the controller 2, but when the controller 2 is in an abnormal condition, they are connected to the (b) side, and the control rack 7 is controlled by a curent adjusting variable resistor 7. Accordingly, the reliability is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electric fuel injection control device that controls the rotational speed of an internal combustion engine by controlling the positioning of a fuel supply amount adjusting element (hereinafter referred to as a control rack).

In order to operate an internal combustion engine in the optimum condition, it is necessary to precisely control the injection amount of supplied fuel according to not only the engine rotation speed but also the operating state of the engine (e.g. temperature, pressure, load torque, etc.) and atmospheric conditions. The effectiveness of this is known. Conventionally, fuel injection pumps for internal combustion engines, mainly diesel engines,
The amount of injection has been controlled by a mechanical cabana that utilizes the balance between the centrifugal force of a flyweight that rotates in conjunction with the accelerator and stops with the engine's drive shaft, and a spring.

Such mechanical cabanas lack flexibility in cabana characteristics;
When considering one of the above-mentioned conditions, for example, the temperature of the engine cooling water, attempting to accurately control the fuel injection amount according to this temperature has the disadvantage that it becomes mechanically complex and extremely difficult to implement.

In recent years, as black smoke regulations have become stricter, it has become necessary to more precisely regulate the maximum injection amount for each engine speed, and to improve cold startability, it has become necessary to increase the starting amount at any temperature. In response to requests such as the desire to perform high-speed operation and to keep the idling speed as low as possible in order to improve fuel consumption, electronic governors using a program control system using a microcomputer that can arbitrarily select governor characteristics are attracting attention. It has been. However, an electronic control unit (hereinafter referred to as "electronic control unit") that calculates a target value for the control rack position according to input information such as accelerator opening speed, temperature, and pressure, and controls it to eliminate the difference between this target set value and the actual value. For electronic governors equipped with controllers (referred to as controllers), it is necessary to add new sensor and actuator parts, and in the unlikely event that there is an abnormality in these parts or a controller abnormality such as a runaway program due to electromagnetic interference, etc. This not only interferes with the stable operation of the engine, but also increases the possibility of accidents such as engine runaway. In order to prevent such accidents, the electronic governor has an abnormality detection function, and if an abnormality occurs, it can cut the supplied fuel and stop the internal combustion engine appropriately. It is desirable to be able to operate the engine even if the engine performance is not optimal.

An object of the present invention is to eliminate the drawbacks of the mechanical governor described above, and to have a controller mainly based on program control for controlling the positioning of a control rack, and an actuator driven by the output signal, and to control the rotation of a diesel engine. In an electronic governor for controlling the number of controllers, a stopper mechanism for restricting the control rack to a certain position and a means for separating the controller and actuator circuits and supplying current to the actuator separately from the controller are provided. An object of the present invention is to provide a fuel injection control device that can supply fuel to an engine even when a roller is disabled.

Hereinafter, the invention will be described in detail using the drawings. FIG. 1 is a schematic diagram of a configuration showing an embodiment of the present invention. 1 is an information input signal corresponding to engine speed, accelerator opening, rack position 2, Isoseki cooling water temperature, atmospheric temperature, etc. 2 is the input stage 21. This is a controller consisting of a control section 22 and an output stage n. The control unit 22 uses, for example, a microcomputer that can calculate the target position of the control rack for adjusting the fuel injection amount in accordance with the information input signal IK, and can control the difference between the target setting value and the actual value to zero. This is the arithmetic control and control section used, which performs programmatic arithmetic control and also has the function of determining failure or abnormality of one information input signal 1 and checking for runaway of the program. Further, the output stage n of the controller 2 is a port for outputting the calculation and judgment results of the control section 22, and the output signal 27 is sent from this output stage.

The output signals U and 5 are the power transistors Q1 and 5 of the power amplifier 3 for driving the actuator 4 operating the control rack. Connected to 2. Further, the output signal 26 is a signal that transmits the result of the determination made by the control unit 22 as to whether or not there is a failure or abnormality in the information input signal 1. The output signal 27 is the output signal as a result of checking for program runaway in the control section 22, and is connected to the abnormality detection section 5 together with the output signal 26.

Here, the output signal 27 sends out a pulse signal with a signal width of approximately 1 m5ec at a cycle of approximately 15m5ec when the program is progressing normally, and when the program becomes abnormal due to runaway etc. It works so that the signal is interrupted. The abnormality detection section 5 includes an abnormality detection circuit 51 configured with a retrigger type monostable multi-by-break, etc., which inputs the output signal 27 and outputs a ll0N signal when abnormal and a fi l I + times signal when normal, and an OR. A circuit 52, an electromagnetic relay 53, and a switch element 54 that drives the electromagnetic relay.
It consists of

Here, the OR circuit 52 takes the output signal of the above-mentioned abnormality detection circuit 51, the output signal station of the controller 20, and the start signal 55 interlocked with the engine KEY switch, and if one or more of these signals is When the temperature reaches 111K, the switch element 54 becomes conductive. Contacts 8W1 and SW2 that operate in conjunction with the electromagnetic relay 53 are inserted between the power amplifier 3 and the actuator 4, and between the controller 2 and a subsidiary of the power source 6, such as a battery. SW here
1 has two contacts a and b, which are normally connected to the a side, and the actuator 4 is driven by the output of the controller 2. Further, in the case of an abnormality, it is connected to the b side and the actuator 4 is driven via the variable resistor 7 for current adjustment. SW2 also has contacts a and b, and when it is normal, it is connected to the a side, and the + pole of the controller 2 and power supply 6 are connected, but when it is abnormal, it is connected to the b side, and the position of the control rack is set to a certain value. A voltage is supplied to the stopper mechanism section 8 for limiting the voltage.

Next, the configuration and operation of the actuator 4 and stopper mechanism section 8 of the embodiment will be explained using FIG.

The actuator 4 has a fixed yoke portion 41 that also serves as an outer cover.
A cylindrical permanent magnet 42 is attached to the inside of the cylindrical part 0, a movable part (2) with a coil 43 fixed thereto is provided inside the permanent magnet, and a tension spring is attached to the inside of the movable part via a magnetic path member 45 that also serves as a guide. 46 is built-in, and
A controller 9 for operating the injection 1 of the supplied fuel is fixed to the actuator 4 by a connecting pin 10.

In such an actuator configuration, the coil 43
When a current is applied to the movable portion I, thrust is generated in the movable portion I, the movable portion 44 moves, and the position of the control rack 9 can be changed.

Furthermore, as can be seen from the configuration of the actuator 4, by changing the direction of the electric current DR flowing through the coil, the thrust direction of the movable part 44 changes, and the supplied fuel is changed to C as shown in the figure (in the case of arrow 9I, the amount of fuel is increased). , in the case of arrow a92, the fuel decreases and if no current flows through the coil 43, the thrust is lost and the control rack 9 is pulled back by the action of the tension spring 46 until the fuel is cut off.

The stopper mechanism section 8 is composed of an electromagnet having a movable plunger relationship with a coil 81, a fixed magnetic path member 82, an arm 8 and a fixed support pin 85 for predetermining the positional relationship between this electromagnet and the above-mentioned actuator. Ru.

In the configuration of the embodiment described in FIGS. 1 and 2,
When some abnormality is confirmed in the program abnormality detection circuit 51 of the controller 2 or the abnormality detection section 5, the electromagnetic relay 53 is activated by the conduction of the switch element 54, and the switching S
The actuator 4 is disconnected from the controller side by the WI, and becomes ready to be supplied with power via the variable resistor 7. At this time, the thrust of the movable member of the actuator 4 is
The variable resistor 7 is set so that the tensile force of the spring 46 is smaller than
By increasing the resistance value, the supplied fuel is cut. The other switch SW2 stops the power supply to the controller 2, and also stops the stopper mechanism section 8.
It becomes possible to supply power to the coil 81 of.

When a single current flows through the coil 81, the plunger 83 hits the fixed magnetic path member 82 and stops due to electromagnetic action, so the control rack 9 connected to the movable part 44 of the actuator is moved to a position predetermined by the shape and dimensions of the arm 84. will be limited to.

Next, by decreasing the resistance value of the variable resistor 7, the flow of air flowing into the actuator 4 is increased, and the actuator L
- When the thrust of the movable part 44 becomes larger than the tensile force of the spring 16, the control rack 9 moves in the direction in which the supplied fuel becomes magnetized, making it possible to supply fuel again and operating the internal combustion engine. It will be possible. Here, the resistance (angle setting) of the variable resistor 7 may be configured such that it can be arbitrarily set by operating a setting knob provided on the operation panel of the driver's seat, or depending on the application, the desired resistance value may be determined in advance. It is better to set the value and fix it at that value.

According to this invention, it has a controller mainly based on program control for controlling the positioning of the control 1 call rack, and an actuator driven according to the output signal,
In an electronic governor that controls the rotation speed of an internal combustion engine, there is a stopper mechanism for limiting the controller speed to a certain position, and a circuit that connects the controller and the actuator to the actuator (separately from the controller). (Since the configuration is equipped with a means that can supply current and a rising detection circuit that detects 5'L9 including program runaway of the controller, flexible but banner characteristics can be obtained and it can also be used to detect program runaway. Even in the event of a controller failure or sensor failure, fuel can be supplied to the internal combustion engine, which has the effect of, for example, making it possible to move the vehicle to a point where it can roam.

In the above embodiment, the actuator 4 is a moving coil (electrodynamic) type equipped with a permanent magnet. However, the actuator 4 is not limited to this type, and for example, an ordinary electromagnetic type, a steering wheel, a motor, etc. can be used. It's okay.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of the configuration of an embodiment of the present invention, and FIG. 2 is a diagram of the configuration of an actuator and a stopper mechanism. 2: Controller, 4: Actuator, 5: Abnormality detection section, 7: Variable resistor, 8: Stopper mechanism section, 9: Controller knob. Ya1 Illustrations 2(3)

Claims (1)

[Claims] 1) An electronic control circuit for controlling the positioning of a fuel supply amount adjustment element based on information input signals such as an accelerator opening signal and a signal corresponding to the rotational speed of an internal combustion engine, and an output signal thereof. A fuel injection control device for controlling the rotation speed of an internal combustion engine, comprising an actuator driven by the actuator; The electronic control circuit and the actuator circuit are separated from each other, and a means for supplying a single current to the actuator is provided separately from the electronic control circuit, so that fuel can be supplied to the internal combustion engine even when the i11 electric power distribution control circuit is disabled. A fuel injection control device for an internal combustion engine, characterized in that: 2. In the device described in claim 1, the means for supplying one current to the actuator separately from the electronic control circuit includes a variable resistor so that the current value can be varied, and the resistance value can be set using the operation panel. 1. A fuel injection control device for an internal combustion engine, characterized in that the control can be performed by operating a knob provided in the engine.